- Messages
- 10,941
- Location
- My mother's basement
rlk said:Actually only the edges are exposed to light as the roll of ribbon sits exposed while the interior portions are covered by multiple layers. Hence fading due mostly to UV from light exposure shows up as slightly faded edges. You may experience the same phenomena in a much faster time frame if you have used roll film(with the paper backing such as 120/220) and load and unload under bright conditions. Shows exposure on some of the edges when developed.
Makes sense, although I have seen whole (entirely unused) rolls of ribbon with only the edges discolored. But both edges. Could be that those rolls were were stacked atop one another or shelved side by side or packed in fairly tightly in one manner or another (likely, that), but I'd think that if light had reached the edges, at least a portion of the outermost layers would also have been exposed to light. And it seems that only one edge would be discolored, the one that was exposed to light, unless that roll was left upright by its lonesome near some source of sunlight.
If what I've seen is fading due to exposure to light, it didn't manifest itself in a lighter color, but rather a reddish tint. (I'm talking lighter colored ribbons here. If it has happened with darker ribbons, well, I couldn't see it.) I suppose (pure speculation) that light has different effects on different dyes, so washing out one shade may leave a redder color visible. [huh]
It's also possible that gunk in the air has settled on the rolls over the years and is oh so slightly visible as a discoloration at the edge. But then, I'd think that in that case the discoloration would be only on the upper edge of the uppermost roll in the stack (or what had been the uppermost roll on the stack, when those rolls of ribbon were left undisturbed for an awfully long time), and that's not what I see.